Electrical toilet flush systems are becoming increasingly popular, which invariably are powered by the mains power (via an AC/DC voltage adaptor) and/or incorporate a motor-driven flush valve. The mains power may not be available in a bathroom or the provision of mains power connection in a bathroom requires extra safety installation (e.g. use of an earth leakage circuit breaker). The installation of a motor-driven flush valve can be relatively complicate and/or expensive, as it often involves the use of a speed-reduction gearbox. In general, manual override is not always possible, and this can be rather inconvenient in the case of power failure.
The invention seeks to mitigate or to at least alleviate one or more of such problems and/or shortcomings by providing a new or otherwise improved flush valve assembly and toilet flush system incorporating the same.